sup guys...some help, advice, opinions wanted for this matter....the basic run down is..my car is acting all jacked...why? no damn clue
-the car was at my friends shop. While the car was stationary, the motor was revved up to about 4k on a conservative throttle %. suddenly, the motor freaks out!..sounds like it suddenly ran on 3 cylinders, cant hold idle, lumpy, choking and then dies out. tried starting her again...same story...chokes out then dies. the motor has been broken in properly after the build, tuned and driven without any headache for the entire '05 year to date.

here is what we have trouble shot so far-
checked/ swapped plugs, wires, distributor, ecu's, did compression test-225psi all the way across. did a leakdown test-all 4 cyl 100% perfect, check valve clearance, swapped MAP sensors, checked fuses, no vaccum leaks, proper oil and water levels, checked injector power signal, cleaned and inspected injectors, swapped fuel regulators, all four's get spark, no timing belt or sprocket splipage

symptoms- we take the plugs out...clean them, put them back in, fire it up a couple times...pul the plugs back out...coated completely BLACK...
i cant understand whats going on...at least so far the motor seems healthy...

-car 93 eg si
-built jdm b18c gsr
-11.5 comp @ 81.5mm bore
-hondata s200

 

i had the same problem with one of my cars.

I would think your washing a cylinder out, and if its running that black, its way too rich.

if it has a chipped ecu or a BASEMAP ecu in it, unplug it, get a STOCK STOCK STOCK ECU and plug it in.

i had a motor i recently built that did the EXACT same thing. except i got low compression on one cylinder. i freaked out thought i was gonna have to tear it down, then i drained the oil, it was BLACK after like 10 min of run time, yet tehre was no metal shaving in it. the plugs were black too.

I swapped in a stock ecu and put it on our dyno and ran it for 30 min and magically it went from 3 cylinders and not idling to running great. Compression numbers jumped up alot as well.

I have seen cars that ran and were broken in properly do the same thing after they sat for awhile as well.

 

i havent drained the oil yet...however..i went through a couple of ecu's...
the car was tuned with a hondata p28
i used a stock p28 and p72 and still no luck
thanks for the tips tho...i'll try ecu's again..and see what happens..
thanks alot...

 

btw..the motor shakes violently....scary status....